Lengthy "Daisy Chain" Transplants Possible From One Altruistic Donor Kidney
March 11, 2009- A new variation in kidney paired donation (KPD) — pioneered and developed at Johns Hopkins — could theoretically generate an endless number of transplants, researchers report.
The possibility of sparking “daisy chain” transplants, described in the March 12, 2009, issue of the New England Journal of Medicine (NEJM), was prompted by reports of one round of 10 kidney transplants, all generated from a single kidney donated by an altruistic donor, says Robert Montgomery, M.D., Ph.D., transplant chief at the Johns Hopkins University School of Medicine and senior author of the study. An altruistic donor is someone willing to donate a kidney to any needy recipient.
What the authors dubbed as nonsimultaneous, extended, altruistic donor chain (NEAD) begins with a kidney from an altruistic donor that is compatible and transplantable in a patient who has a relative or friend willing to donate, but whose kidney is not compatible by blood or tissue type. Once the altruistic donor kidney is matched up and transplanted, the kidney from the willing donor from the original incompatible pair goes to solve the problem of another incompatible donor-recipient pair and so on, theoretically endlessly, limited only by the number of recipients and possible, available matches.
The 10-way NEAD or “daisy chain” outlined in the NEJM article started at an Arizona hospital in July 2007. The majority of the subsequent transplants including the most recent, 10th transplant in the chain, were performed at The Johns Hopkins Hospital.
NEAD builds on the concept of so-called domino kidney plant donation. Developed and pioneered at Johns Hopkins, domino KPD uses a kidney from an altruistic donor that goes into a pool that includes a finite number of incompatible donor-recipient pairs and a patient that’s next on the United Network for Organ Sharing (UNOS) organ recipient list. Doctors and transplant coordinators can then match donors with recipients inside of this pool, striving for the best possible match based on blood and tissue antigen testing. Although effective, this process is limited by the number of available incompatible pairs, good matches and available operating rooms because all the surgeries are performed on the same day.
“When an altruistic donor starts a kidney donation chain, it is no longer imperative that the transplants are done simultaneously,” says Michael A. Rees, M.D., medical director of the Alliance for Paired Donation and lead author of the study. This is beneficial because it does not require multiple surgeons and operating rooms. It also eases the complicated matching required when there are multiple donors and recipients needing same-day surgery. Alliance for Paired Donation is a consortium of transplant centers that maintains a database of incompatible donor-recipient pairs.
“NEAD chains are the latest of a series of important breakthroughs in transplantation that will significantly increase the number of life-saving organs available to hard-to-match patients, many of whom die while waiting years for a kidney,” says Montgomery.
Johns Hopkins surgeons performed one of the first KPD transplants in the United States in 2001, the first triple-swap in 2003, the first double and triple domino transplant in 2005, the first five-way domino transplant in 2006 and the first six-way domino transplant in 2007. Johns Hopkins also led the first multihospital, transcontinental three-way swap transplant in 2007.
Additional information about domino KPD, the Johns Hopkins Hospital Transplant Division and UNOS, can be found at the following Web sites.
Eric Vohr 410-955-8665; email@example.com